<!DOCTYPE html>
<html>
<head>
	<meta charset="utf-8">
	<title>unicode编码表</title>
	<script type="text/javascript">
		var num1 = +prompt("请输入一个分数");
		/*
		
		if(num1 < 100 || num1 > 0 || !isNaN(num1)){
			if(num1 == 100){
			alert("你满分");
		}else if(num1  >= 80){
			alert("优秀");
		}else if(num1  >=  60){
			alert("及格");
		}else{
			alert("差");
		}
		}
		else{
			alert("输入数字非法");
		}
		*/
		
		/*
		switch(num1){
			case 60:
				alert("及格");
				break;
			default:
				alert("不及格");
				break;

		}
		*/

		switch(true){
			case num1 == 100 :
				alert("满分");
				break;
			case num1 >80 :
				alert("优秀");
				break;
			default:
				alert("需要学习");
				break;
		}



	</script>
</head>
<body>

</body>
</html>